In "Early Autumn," by Robert B. Parker, the private eye has come a long way from the dissolute days when he was a hell-raising, hard-drinking womanizer with a license to carry a gun. Spenser, Mr. Parker's detective, is a baby-sitter in the seventh novel of this popular series.

He salvages Paul, a 15-year-old boy whose divorced parents each want him only to spite the other. Paul is "thin, nasty, apathetic and withdrawn." In a surge of supererogation, Spenser takes him to Maine and starts him running, boxing, lifting weights, reading, talking, listening to music and building a house. As you can see, "Early Autumn" is a bildungsroman.

In spite of Spenser's baby-sitting, he's a pretty rough customer and "Early Autumn" mixes violence and compassion in a better-than-average way. The book has one small flaw and one not so small: Mr. Parker says jab when he means a straight...